View Full Version : Crossover refurb - Help needed please
Just prepping the IMF TLS50 for their capacitor change, Got the crossovers out, but they have foam pads glued on the backs and I can't see any way of doing the job without removing all the foam completely. I scraped off a corner and that was enough to show it would be a long job. Is there any quick way to remove this? It is securely stuck down and will only scrape off in bits.
might only have to take off the bits where the caps are if you can see where the solder points are. you could soak it in something to soften it I suppose, as long as you dry it thoroughly. We used to was panels from tvs in soap and water and a toothbrush and then dry them overnight on a radiator back in the day .
not sure I can do that - there are 4 inductors plus another tube thing that I have no idea about in addition to all the capacitors. I can rip the bulk of it off fairly easily but that still leaves a thin layer across the surface.
Guess you'll need to do it the old fashioned way and scrape and pick.
walpurgis
04-08-2016, 21:10
Bung some photos on Martin.
was wondering if heat might loosen glue, but it may do more harm than good tbh. they must have been like this for years. I'd still maybe try a hot damp sponge on top and see if it softens it a bit
walpurgis
04-08-2016, 21:37
Spray furniture wax polish softens many adhesives, like those on sticky tape, labels and contact adhesives. Takes a while, but does not damage surfaces.
not sure I can do that - there are 4 inductors plus another tube thing that I have no idea about in addition to all the capacitors.
The 'tube thing' is likely another capacitor or a resistor. Crossovers are all pretty much inductors, capacitors or resistors.
100% Analogue
No, the tube is very odd. Looks like a little copper coil covered in a gray housing. It isn't a capacitor. It might be a tiny inductor. I'll try and post some picture tonight. I've worked out from the values and a process of elimination where all the replacement caps are supposed to go. I'm just worried about damaging the circuit board tracks when scraping off all the sponge.
Hmm.. how odd, yeah, post a picture - perhaps it is an inductor but one would expect the rod to be inside the coil.
I would be tempted to hard-wire the circuit and not use the circuit board.
100% Analogue
I've considered hard wiring it all but I would still need to clean off all the sponge/foam to get the inductors off the board. Also with 4 drivers a side there are alot of wires to match up. I've hard-wired crossovers before but only with two-way speakers and that was over 20 years ago.
http://i903.photobucket.com/albums/ac233/Macca_photos_2009/DSC_0097.jpg (http://s903.photobucket.com/user/Macca_photos_2009/media/DSC_0097.jpg.html)
http://i903.photobucket.com/albums/ac233/Macca_photos_2009/DSC_0098.jpg (http://s903.photobucket.com/user/Macca_photos_2009/media/DSC_0098.jpg.html)
http://i903.photobucket.com/albums/ac233/Macca_photos_2009/DSC_0100.jpg (http://s903.photobucket.com/user/Macca_photos_2009/media/DSC_0100.jpg.html)
Arkless Electronics
05-08-2016, 17:19
If the thing at the bottom of the last picture is the mystery part then it's a wirewound resistor. About 5 Watt rating from the best I can judge of scale to other parts. It should have the resistance value on it... It's unlikely to need replacement.
Thanks Jez - A resistor makes sense. I don't have a replacement part for that so it won't get changed.
Just realised I didn't take a picture of the foam backing.
brian2957
06-08-2016, 07:12
I hope you've got the cakes in for James coming Martin . Have a good day mate . Wish I was there . I'll be watching to see how the GL75 compares to the Technics .
Hope the crossover refurb is painless and successful :)
Those Elcaps have various opinions - my BC2 crossovers have them. [edit] - No they don't, and I was also wrong as to the exact makeup of these caps - apologies all and thanks for correcting me Jez - the BC2's definitely have film caps in them, so shouldn't age the same and it seems they only go off badly if they crack. The other tubular bits are the inductors, so leave alone please. These crossovers were attached using foam to help prevent vibration I understand.
Macca, the TLS50's are what they are, one of IMF's smaller earlier models from 1973 or thereabouts, judging from the drivers used. You cannot change them into something *tons* better 'cos the drivers aren't good enough - and I'm not being a wet blanket, just hopefully putting things in perspective. the only way to improve bass is to add damping to the line so the driver doesn't see the end of the line so easily (this isn't one I think would benefit from removing all the foam and wadding inside as the midrange would be ruined by the added boom - I think - )
Macca, the TLS50's are what they are, one of IMF's smaller earlier models from 1973 or thereabouts, judging from the drivers used. You cannot change them into something *tons* better 'cos the drivers aren't good enough - and I'm not being a wet blanket, just hopefully putting things in perspective. the only way to improve bass is to add damping to the line so the driver doesn't see the end of the line so easily (this isn't one I think would benefit from removing all the foam and wadding inside as the midrange would be ruined by the added boom - I think - )
Yes they are 1973. I'm not modding them in the slightest and I don't expect to make them 'tons better' - I'm just restoring to factory spec as the capacitors are now way outside tolerance. I do expect them to compare favourably with a modern speaker costing in the region of £5K* since if they were made now they would cost at least that amount new.
Even with the current dodgy caps it is clear they have great potential. And yes, TL bass is TL bass and has it's own issues, but if you can name a speaker that does perfect bass please do. I've never heard one.
*Some would say that is not so difficult a task ;)
PM'd you with some advice Martin.
Arkless Electronics
06-08-2016, 14:17
Those Elcaps have various opinions - my BC2 crossovers have them. they're NOT electrolytics, so shouldn't age the same and it seems they only go off badly if they crack. The other tubular bits are the inductors, so leave alone please. These crossovers were attached using foam to help prevent vibration I understand.
Macca, the TLS50's are what they are, one of IMF's smaller earlier models from 1973 or thereabouts, judging from the drivers used. You cannot change them into something *tons* better 'cos the drivers aren't good enough - and I'm not being a wet blanket, just hopefully putting things in perspective. the only way to improve bass is to add damping to the line so the driver doesn't see the end of the line so easily (this isn't one I think would benefit from removing all the foam and wadding inside as the midrange would be ruined by the added boom - I think - )
Oh yes they are!
I've corrected the above - thanks Jez. I checked my pics of them- the BC2's have Erie film caps in them :scratch:
Sorry Martin, I'm a bigger idiot today than I usually am. Stone - crawl - under - hide...
Arkless Electronics
06-08-2016, 16:29
I've corrected the above - thanks Jez. I checked my pics of them- the BC2's have Erie film caps in them :scratch:
Sorry Martin, I'm a bigger idiot today than I usually am. Stone - crawl - under - hide...
I've got some BC2's n all... they're nice. And yes they use film caps.
I've corrected the above - thanks Jez. I checked my pics of them- the BC2's have Erie film caps in them :scratch:
Sorry Martin, I'm a bigger idiot today than I usually am. Stone - crawl - under - hide...
No worries Dave. So many speakers, so many years,,, I know what it is like, the old memory plays tricks.
The caps going off in these speakers is a well known issue which is why Falcon do a set of replacements which I acquired several months ago. I was hoping to have to put as little effort into the actual replacing as possible but now it seems that plan has been thwarted.
There may be an adhesive remover that could clean the back of the board up?
oceanobsession
07-08-2016, 10:03
petrol or paraffin will break down glue , paint it on and leave for a while , phil.
Thanks Phil. Not sure where I can aquire either. Suppose I could siphon some out of the neighbour's car...
Lighter fluid for a Zippo.
Now that I do have. It won't affect the circuit board or the components though?
Arkless Electronics
07-08-2016, 13:29
Now that I do have. It won't affect the circuit board or the components though?
It should be fine.
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